For the last year and a half, Guster, a popular indie rock band, has been on a mission to spread green wisdom to its fans along with its music. On each of their stops, band members invite their audiences—mostly undergrads who turn out for their Campus Consciousness Tour—into their bus, where they tout the benefits of biodiesel, show off their biodegradable tableware (made from corn and potatoes), explain that they use only rechargeable batteries onstage and soy ink in their liner notes, and urge fans to buy carbon credits to offset their car rides to the concert. “We don’t want to be soapboxy, because that could backfire,” says guitarist and vocalist Adam Gardner. “But it’s something we just want to make available to people. And if they’re not interested, then here’s the next song.”

There’s no question that young people have woken up to the realities of global warming. A new poll from Gallup shows that 44 percent of those between the ages of 18 and 34 believe we need to take “immediate, drastic” action on the environment, compared with 38 percent of those between the ages of 35 and 54, and 33 percent of those 55 and older. A higher percentage of young people also say they understand global warming well and believe it results from human activities as opposed to natural changes in the environment. “We’re on the verge of a sea change in young people’s engagement with climate and other environmental issues,” says James Gustave Speth, dean of Yale University’s School of Forestry & Environmental Studies. “I’m predicting a groundswell that will become a major force in politics.”

Those too young to remember the legislative victories of the 1970s, like the creation of the EPA and the Clean Air and Clean Water acts, have come of age in a world where recycling, organic food and annual Earth Days are a given. But they may also be the first generation to feel the effects of climate change so dramatically, from 70-degree winter days in the Northeast to the Christmas 2004 tsunami to Hurricane Katrina. Those events, combined with a sense of a lack of leadership in Washington on environmental issues, have galvanized young people. Many say global warming has become the campus cause of the decade, picking up where Vietnam, apartheid and AIDS awareness left off in the ’70s, ’80s and ’90s. “There is a deep misconception about our generation and what drives us,” says Jared Duval, 23, national director of the Sierra Student Coalition, the national student chapter of the Sierra Club. “So many people assume that we are apathetic because we aren’t spending all of our time on antiwar marches the way our parents’ generation did. That is not the result of apathy, it is the result of foresight.”

Reared on MTV, YouTube and celebrity magazines, young people are attacking the environmental movement with a different strategy than those who became politically active in the 1970s. Speth says the approach is a more subtle one. Some call it “light green.” Rather than boycotting companies and organizing violent demonstrations, many activists are marshaling savvy marketing and technology skills in order to attract a wider, more diverse group of people to the cause. “We’re hopefully trying to move the conversation into the mainstream,” says Lauren Sullivan, who, with her husband, Guster’s Gardner, founded Reverb, an organization that helps musicians like Sheryl Crow and Barenaked Ladies make their tours more green. The group sets up tents before each show, where audiences can meet representatives from local environmental groups and sample organic products.

Changing the stodgy image of the environmental movement is at the heart of what many young activists are trying to do. Danny Seo, 29, is a pioneer in the field of eco-living. Born on Earth Day, he started his first environmental organization at 12 and then worked as an environmental lobbyist in Washington during his college years. But he had a twin passion for design and home improvement, and chose that path instead. Now a noted eco-lifestyle expert and author of a popular series of books on environmentally friendly décor and entertaining called “Simply Green,” he says he doesn’t regret taking the softer road. “On the surface, it may seem silly to be focused on colors and fabrics and doing a gift-wrapping book, but there is a meaning. For a long time I think people have been saying you gotta go green because it’s good for you, because it’s good for the planet. But no one wants to do that for that reason alone. You have to make it affordable and stylish and exciting, because at the end of the day, that’s what good marketing is.”

Along with lifestyle experts, the new environmental movement has spawned its own online magazines dedicated to green living. Lime.com, started by former Oxygen Media executive C. J. Kettler, attracts young people with a fresh combination of short videos, blogs about such things as green renovations and finding the best organic baby food, and funny news items about celebrities’ efforts to be eco-friendly. “Historically, the image of the environmentalist in this country has been something of a scold—preachy and self-righteous,” says Chip Giller, 36, founder of the environmental news site Grist.org. “We try to remind people that [environmentalism] isn’t all about punitive things. It’s not all about a reduction in your lifestyle.” Grist, with a readership of 800,000, is often called “The Daily Show” of the green space because it uses clever writing and wit to get younger people involved. One of the group’s claims to fame is turning a Chevy Tahoe ad campaign on its head. After Chevy asked the public to create and post their own commercials for the new car on Chevy’s Web site last spring, Grist posted its irreverent take on the ad, inspiring hundreds of readers to do the same. Soon the Chevy site was overwhelmed with videos bearing slogans like “Don’t Let All Those Deaths Go to Waste” (the cynical meaning: soldiers are dying for oil in Iraq, so you might as well fill up your tank). “We use humor as a way to get through the jadedness that some people have about this issue,” says Giller.

That’s not to say the movement doesn’t have its more traditional activist side. Duval’s Sierra Student Coalition is now active on more than 300 campuses across the country, where students are pushing their universities to reduce their global-warming pollution to zero by conserving energy and getting power from clean, renewable sources like wind and solar. One student Duval is working with is Lauren Stuart, a Louisiana State University junior. After seeing her campus nearly wiped out by Hurricane Katrina, Stuart founded the first environmental group at her conservative school. So far, she has won a pledge from LSU’s administration to build more bike routes and shut a large part of its campus to automobiles by August.

Other activists have turned to money to exert pressure. Mark Orlowski, a 2004 graduate of Williams College, founded the Sustain-able Endowments Institute in Cambridge, Mass. In January the group put out its first annual College Sustainability Report Card, in which it gave grades to the 100 largest-endowed schools based on such indicators as green buildings, recycling, availability of local or organic food and how ecofriendly their investments are. But the group’s main mission is to get universities to use their power as big investors to urge companies to implement more sustainable business practices.

Some are critical of this softer approach. Fred Meyerson, a professor of demography, ecology and environmental policy at the University of Rhode Island in Kingston, says that many groups have started to shy away from important environmental issues like population control because they’ve deemed them too contentious. “They don’t really push the envelope the way people did in the ’70s and ’80s.” And, whatever the approach, even the most optimistic of Gen-Xers aren’t convinced that environmentalism is here to stay. “We need to make sure this environment boom isn’t just a two-year trendy thing, but that green becomes embedded in our culture,” says Grist.org’s Giller. No matter how it gets done.